Police in Islington have charged a 15-year-old female from Croydon with assault and possession of an offensive weapon.
She will appear in custody at Highbury Youth Court on Friday, 24 February.
This follows an investigation into footage which was circulating on social media showing two girls fighting. Officers established that the incident happened in Islington in January this year.
A 15-year-old girl was arrested on Wednesday, 22 February and charged as above.
Enquiries continue.